1. Field of the Invention
Embodiments of the present disclosure relate to environment monitoring technology, and more particularly to a cleanliness monitoring system and the cartridges thereof
2. Discussion of the Related Art
Clean environments are needed for many technical fields, especially for factories manufacturing liquid crystal panels. The glasses for liquid crystal panels are transported by cartridges, and each of the cartridges may transport a few tens of glasses. The cartridges are transported by automatic material handling systems (AMHS) to corresponding stockers. The glasses are then retrieved from the cartridge by distributing devices in turns for corresponding manufacturing processes. After the manufacturing process, the glasses are transported back to the cartridges in turns, and the AMHS further transports the cartridge to another stocker for a next manufacturing process. The stocker and the tunnels connecting the stocker and the cartridges are part of the AMHS.
In manufacturing processes, the cleanliness of the environment directly affects the defective-free rate of the liquid crystal panels. As the defective rate results in significant costs for liquid crystal panels, each of the manufacturing processes of the liquid crystal panels has strict demands regarding the cleanliness. Especially, as the liquid crystal panels are deposited in the material handling system for the longest time, the cleanliness for the material handling system is the most critical one.
Currently, the cleanliness monitoring of the material handling system is conducted by a single measuring device operated by operators. The method has the following disadvantages. First, operators are also pollution sources. Second, the measuring device has to be shut down in some spots so that the capacity is reduced. Third, as the range of the factories is quite broad, a lot of measuring devices and the operators are needed so as to cover the range. For example, at least ten measuring devices are needed for the stocker with a length equaling to 60 meters, a width equaling to 6 meters, and a height equaling to 6 meters. Lastly, as the measurements are conducted by the operators, the hysteresis characteristic caused by the operators may result in the risk of defective rate.